Custom template does not show up in the list (Impress)

I have created a custom template for Impress (extension .otp) and saved it in the path where the templates are located (checked under Tools > Options > LibreOffice ? Paths). No way to get it, it won’t show up even after quitting LO and exiting QuickStarter. How to force LO to recognize the template and add it to the list?
Thank you in advance.

Start the Template Manager (Ctrl+Shift+N), click on tab Presentation, then on MyTemplates. You will see an icon Import. Click it and pick your file.